High Pressure Flow meter

Air?

Vortex shedding. Try Endress + Hauser and Vega (Usual disclaimer).

for Nitrogen & Air both

1) Clamp-on ultrasonic (Siemens/formerly Controlatron) is known to work on both liquids and gases and does not require insertion into the pipe or dealing.

http://www.automation.siemens.com/w1/automation-technology-clamp-on-flow-18668.htm

2) Flanged orifice plate and DP transmitter

Try with Coriolis flowmeters(Daniels from Emerson).

thanks everyone, will let you know of my purchase

Hi santy

Looking at the responses all the usual suspects are there but you will get clearer and more useful answers if you give more detail.

We now know you are measuring air / nitrogen

You say up to 4000SCFH (by the way at 200 barg I make this 225 kg/hr and 0.6Am3/hr which is a tiny gas flow)

However as well as the actual flow we need to know the range ie is it 10 - 4000, 100 - 4000, 3000 - 4000

A orifice plate is the simplest cheapest device but has a limited turndown so probably 600 - 4000

Coriolis meters have huge turndowns the others somewhere in between

What accuracy do you need. If people are paying for the gas then you need custody quality maybe a coriis is justified, but if its just for bleeds to pressurise vessels and for internal accounting maybe the accuracy of a orifice is adequate. Again vortex meters etc are somewhere in between.

How much money do you have? An orifice and coriolis meter give the extremes of price.

A clamp on ultrasonic does not impact the exsting system. It can be installed without shutting down your current operation and without the need to depressurise your piping. As you operate at 200 bar this might be an issue.

When comparing costs make sure you include the shut down cost for the other meters. ie an orifice will be cheapest but say it cost $1000, the clamp on ultra sonic costs $10,000 and shutting down for a day to install the orifice costs $1million its easy to see which meter you should install.

Personally I would not look at coriolis for gases even hi pressure gases. The density of 200 barg gas is in the range of liquid densties so it should work but it makes me nervous but thats just a personal preference

Hi Simon,

Thanks for the detailed reply. Well i am trying to design and manufacture a high pressure regulator say with 6000 psi inlet and outlet 300-6000 psi range. Size is about 1/4".

I need to get the flow curve of this regulator and hence the flow meter. I hope you could suggest me one better. Budget is close to 5000 USD.

Thanks

Hmm now I am stymied as Instruments are not my area of expertise.

Firstly I would say you MUST put the meter in the upstream piping. All meters work best when there are as few variations as possible. If you are trying to put a flowmeter in a circuit with an operating pressure 300 - 6000 psi then

Orifice Plate, Vortex Shedding, or similar devices will not work as the pressure and consequent density difference for the operating point makes it too complex for a meter. An orifice uses a velocity head to convert to a pressure drop then infers a flowrate. It needs an approximately constant density to work. Whilst you could get some sort of measurement over a 20x range of pressure it wont be reliable.

I dont know for sure about vortex shedding but I would imagine they perform differently as the votices roll off into different density fluids

I have no idea about ultrasonics. I would imagine that a widely changing density will have more impact on the ultrasonic signal than a variation in flow

You have very tiny tubing at high pressure. I am not sure any of these meters can be supplied for that small a fitting unfortunately you will need to speak to the vendors. Maybe you could start with companies that supply lab equipment rather than industrial stuff. Could yu get a more sophisticated version of a rotameter?

I would recommend that you look up krohne flow meter ,they are of great quality.

I would suggest the Cameron DP cone meter. They make a 1/2" meter. You can get it in any pressure rating. It is a DP flow meter. You can use a DP transmitter to take readings and use their sizing program to do the flow rate calculation to get your curve.

It is a DP meter with that will measure your range and not cost you a lot of money. You could get this set up for about 2500 USD or less.

www.c-a-m.com/flo is the website. you can find a local dealer there or contact the Houston office for assistance.